Adoption of U-Boot commit:

| commit f81db56
| Author: Stefan Brüns <stefan.bruens@rwth-aachen.de>
| Date:   Sat Nov 5 22:17:14 2016 +0100
|
|     ext4: Fix handling of sparse files
|
|     A sparse file may have regions not mapped by any extents, at the start
|     or at the end of the file, or anywhere between, thus not finding a
|     matching extent region is never an error.
|
|     Found by python filesystem tests.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>